Pile weatherstrip having a looped barrier fin

ABSTRACT

The object of this invention is to provide an improved pile weatherstrip having a loop-shaped barrier film. The weatherstrip, which is used for sealing openings between fixed and movable members, comprises a backing strip to which is secured a barrier film of loop-shaped cross section formed, for example, from a polypropylene material. The loop-shaped film is formed from a web of material folded upon itself with one end portion thereof secured in various ways to the backing strip and an opposite looped portion extending from the strip.

DESCRIPTION

1. Technical Field

This invention relates to an improved pile weatherstrip for forming adraft excluder around doors and windows.

Pile weatherstripping incorporating an impermeable barrier film or finin sheet form within the pile material has excellent weatheringproperties, but the presence of the barrier film can cause problems,both with sliding windows, whether of the sash type or of the horizontalsliding type, and with the hinged casement and horizontal pivot windows.For example, the presence of the film increases the breakaway forceneeded to reverse the direction of the free end of the film and toovercome the friction between window sash and weatherstrip when a windowis to be opened. Also, the resistance to a member sliding perpendicularto the barrier film when the motion of the sliding member is reversed isfurther increased due to the free end of the film catching in minutegrooves in the surface of the sliding member. Furthermore, if the windowor door is kept closed for a long time, a single barrier film tends totake a set, i.e., it remains in its partially collapsed state, evenafter the door or window has been opened, thus gradually reducing theweatherstrip's performance. Also, in certain situations, the film tendsto collapse or fold over when the weatherstrip is inserted into a groovein a door or window, probably because of reverse bending of theweatherstrip during the insertion process. A further problem with knownpile weatherstrip incorporating a barrier fin is that it is rather stiffand resists compression when a door or window is to be shut. This meansthat to shut the window and compress the strip, considerable force mustbe applied to the door or window.

I have now developed an improved pile weatherstrip incorporating alooped barrier film which reduces or overcomes at least some of theabove problems, the looped film being secured to the backing strip orpile material in various novel ways.

2. Background Art

U.S. Pat. No. 3,745,053 describes a weatherstrip having a backing strip,and two longitudinally extending spaced parallel rows of pile attachedto the backing strip. In one embodiment of the invention, single ordouble barrier fins are interposed in the space between the rows of pileand secured to and supported only by the pile. In FIG. 6, a barrier filmof a different configuration is shown positioned in the space betweenthe rows of pile. The barrier film in this embodiment is in the form ofa web bent back on itself to form a looped end portion extending awayfrom the backing strip. The opposite end portions of the web are spacedfrom the backing strip, and the barrier film is secured to and supportedonly by the pile. Problems that arise in the use of this type ofweatherstrip, for example, are leakage of air and moisture through thespace between the lower end of the barrier film and backing strip, andincreased resilience of the barrier film resulting in excessive leakageof air and moisture past the weatherstrip.

3. Disclosure of the Invention

According to the present invention, I provide pile weatherstrippingcomprising a backing strip which is preferably flexible, and having pilematerial projecting from one of its surfaces, and wherein at least onelooped barrier film or fin is located adjacent the pile and projectsfrom the backing strip in the same direction as the pile material, saidfilm or fin being in the form of a tube or loop.

Preferably, the tube or loop is provided by an extrusion or a singlestrip of material folded into a closed or substantially closedconfiguration, an anchoring end or edge region of the material beingsecured in various ways to the backing strip.

In one construction, it is envisaged that the single strip of materialmay be so formed and folded as to provide a double tube or loop.

In one embodiment, the folded end portions or edges themselves areturned up away from the backing strip.

In some instances, the tube or loop may have apertures formed in itthroughout its length to allow it to collapse and expand. Normally,however, it would only be open at its ends. The tube or loop in certaininstances may also be filled with a collapsible material.

A weatherseal having a looped or tubular type sealing barrier fin hasthe following advantages over the traditional weatherseals with fin typebarriers:

(a) There is no creasing of the barrier when the strip is compressedwith resultant loss of sealing characteristics.

(b) When the weatherstrip is compressed in use it offers less resistancethan traditional weatherseals, and lower compression set due to theresilience of the looped end forcing the looped end back to its originalposition.

(c) The looped barrier is always supported by the pile.

(d) The weatherseal does not suffer from shrinkage.

(e) The weather seal presents low break-away forces to sliding members,and less resistance to movement of a sliding member perpendicular to thebarrier fin when the sliding member is reversed.

(f) The looped barrier acts as a cushion upon closure of a memberagainst it. In this respect the tubular barrier could, in certaincircumstances, be filled with foam or pile.

(g) The flatter and wider sealing surface area of the barrier effects amore positive seal than a single fin-like barrier.

(h) Better sealing in straight compression applications because thelooped end deforms along its entire length whereas the free end or endsof single or double sheet fins could change direction along thelongitudinal line of contact permitting leakage at the points where thechange in direction occurs.

(i) Reduction in noise or squeaking in automotive applications due, forexample, to the looped end deforming substantially along a line parallelto a line bisecting the loop, rather than laterally thereof as in asingle or double sheet fin.

(j) The dead air space in the tubular barrier acts as an accoustic sealas well as a thermal insulator.

(k) Since the tubular barrier is normally open only at its ends,pressure differentials which are set upon opening or closing of themember against which a seal is to be made can be used as a sensor. It isenvisaged, therefore, that the seal could be used as a security system,for example as a burglar alarm, by connecting suitable sensing apparatusto the space within the barrier film.

The invention and its advantages will become more apparent from thedetailed description of the invention presented below.

BRIEF DESCRIPTION OF THE DRAWING

Several embodiments of pile weatherstrip containing a looped barrier finaccording to the present invention are now described by way of examplewith reference to the accompanying drawing, in which:

FIG. 1 is a cross-sectional view of one embodiment of the pileweatherstrip of this invention; and

FIGS. 2-6 are end views of other embodiments of the looped pileweatherstrip of this invention.

BEST MODES FOR CARRYING OUT THE INVENTION

In the drawing, similar or like parts have the same reference numeralsin the different Figures.

Referring to FIG. 1 of the drawing, the weatherstrip has a conventionalflexible backing strip 1 from one face of which the traditional pilematerial 3 of the required height and density upstands in a pair ofspaced rows. Within the space between the rows of pile material, an airimpervious looped barrier 7 of generally tubular or substantially closedconstruction is provided. The barrier 7 is formed from a single strip ofpolypropylene film or other suitable polymeric material or the likefolded through about 180° to form an open end portion comprising twoadjacent free ends 9, 11 secured to the backing strip 1 in known manner,e.g., by two separate welds. Barrier 7 also has an opposite closed orlooped end portion engageable by a closure member, not shown.

Seen in corss-section, the center barrier 7 presents a looped typeconfiguration. Because only the ends 9, 11 of the film barrier 7 of FIG.1 abut the base backing strip of the weatherstrip, the attachment of thebarrier 7 to the backing strip 1 may not be as strong as desired forsome applications.

In the embodiment shown in FIG. 2, the barrier 7 is of tubular formpreferably extruded from a suitably shaped die. The barrier 7 has anarrow flat closed end portion 12 that is welded to backing strip 1.

In the construction shown in FIG. 3, the anchoring end portion comprisesedge regions 13, 15 of the barrier film 7 which overlap each other asshown at 19 making it possible to weld the barrier 7 to the base of theweatherstrip over a considerable area. The folded end portions 21, 23 ofbarrier 7 are turned up away from the backing strip 1. With thisconfiguration, it is proposed that the barrier film 7 be folded by anysuitable mechanism and enter the welding area on a tapered mandrelcantilevered from the mechanism. The welding would be accomplished atthe point of the taper in engagement with the overlapped edge regions.By varying the amount or place at which the edge regions are overlapped,it is possible to position the barrier 7 at the desired height inrelation to the supporting pile 3.

FIG. 4 illustrates a modification of the construction shown in FIG. 3,where the edge regions 13, 15 of the barrier film 7 instead of beingoverlapped are turned outwardly to lie flat against the backing strip 1and are secured to the strip 1 by a double weld. It will be appreciatedthat the height of the barrier 7 can be altered for a given width offilm merely by altering the length of the end portions 21, 23 of thefilm which are turned up away from backing strip 1 without altering thewidth of edge regions 13, 15.

In the construction shown in FIG. 5, a double barrier 77 is provided.Each barrier 77 has a folded end configuration in which the filmmaterial is folded on itself with the end portions 21, 23 enclosed sothat no sharp edge is presented to the opposite member with which a sealis to be formed. This type of configuration can be controlled for theheight above the pile in the same manner as described with reference toFIG. 4. The folded overlapped edge regions of the end configuration canalso be readily welded to the base. In this construction and that ofFIG. 3, the barrier 7 can be attached to the backing strip 1 by a singleweld.

In the embodiment shown in FIG. 6, the end portions 21, 23 of the filmare turned up away from the backing strip, and the two edge regions 13,15 of the film are secured to the backing strip 1 in adjacentrelationship, e.g., by two adjacent welds. This allows a more positiveconnection of the barrier 7 to the backing strip than shown in FIG. 1,for example.

To assist the collapse of the loop(s) and return each loop to itsoriginal shape again after the window/door to which it is secured orwith which it is to form a seal has been closed/opened, a plurality ofapertures 25 as illustrated in FIG. 1 may be provided throughout thelength of the tube. This is not normally necessary, however, if the endsof the tubular barrier are left open. Also, the looped barrier 7 couldbe filled with any suitable collapsible material such as a foam 27, ifdesired, as seen in FIG. 1.

With this invention, compression forces necessary partially to collapsethe weatherstrip when shutting a door or window to which theweatherstrip is fitted are kept low. Also, this type of barrier 7 willoffer a minimum of resistance at the sealing point to a member slidingperpendicular to the barrier when the motion of the sliding member isreversed. This configuration of the barrier will also seal better ininstances where the sliding member is parallel with the barrier.Furthermore, a tubular type barrier 7 will also seal well in straightcompression applications, whereas a barrier with a single or double edgeor edges could change direction along the point of contact, permittingleakage at the point of direction change.

Since the looped barrier film 7 is normally open only at its ends,pressure differentials which result within the barrier upon compressionof the seal and barrier by opening or closing a member can be used as asensor. Accordingly, the seal can be used in a security system, forexample as a burglar alarm, by connecting suitable pressure sensingmeans to the space within the looped barrier film as illustrated in FIG.1.

It is also proposed that a further configuration would have a single ordouble row of looped pile 3 to act as supporting member(s) for thebarrier 7. This would further lessen reversal efforts in applicationswith the sliding member perpendicular to the barrier 7.

The invention has been described in detail with particular reference topreferred embodiments, but it will be understood that variations andmodifications can be effected within the spirit and scope of theinvention.

I claim:
 1. A barrier fin weatherstrip comprising:a longitudinallyextending backing strip; a longitudinally extending row of pile havingone end surface attached to said backing strip and its opposite free endsurface projecting from said backing strip; and a longitudinallyextending anchoring barrier fin of loop-shaped cross-section having alongitudinal end portion thereof secured directly to said backing stripadjacent said pile and an opposite longitudinally extending closedlooped end portion adjacent said free end surface of said pile.
 2. Aweatherstrip according to claim 1 wherein said barrier fin is formedfrom a single web of material folded upon itself to form said loop, andsaid anchoring end portion is an open end portion.
 3. A weatherstripaccording to claim 2 wherein said open end portion compriseslongitudinally extending free ends of said web which are secureddirectly to said backing strip.
 4. A weatherstrip according to claim 3wherein said open end portion comprises longitudinally extending edgeregions secured to said backing strip.
 5. A barrier fin weatherstripcomprising:a longitudinally extending backing strip; a longitudinallyextending row of pile having one end surface attached to said backingstrip and its opposite free end surface projecting from said backingstrip; and a longitudinally extending barrier fin of loop-shapedcross-section formed from a single web of material folded upon itself toform said loop, said looped web having a pair of longitudinallyextending free web ends folded with edge regions thereof in overlappingrelationship and secured to said backing strip, said fin further havinga longitudinally extending closed looped end portion opposite said edgeregions of said web and adjacent said free end surface of said pile. 6.A weatherstrip according to claim 5 wherein the parts of said web endsextending from said edge regions are further folded to extend upwardlyfrom said backing strip adjacent a surface of said web.
 7. Aweatherstrip according to claim 5 wherein the parts of said web endsextending from said edge regions are further folded to extend upwardlyfrom said backing strip adjacent a surface of said pile.
 8. Aweatherstrip according to claim 5 wherein said single web is folded uponitself to form a pair of loops in side-by-side relation.
 9. Aweatherstrip according to claim 5 or 8 wherein said loop or loops haveapertures extending therethrough throughout their length to allow saidloop or loops to collapse and expand.
 10. A weatherstrip according toclaim 5 or 8 wherein said loop or loops are filled with a collapsiblematerial.
 11. A weatherstrip according to claim 5 or 8 wherein said loopor loops are connected to a pressure sensor.
 12. A barrier finweatherstrip comprising:a longitudinally extending backing strip; alongitudinally extending row of pile having one end surface attached tosaid backing strip and its opposite free end surface projecting fromsaid backing strip; and a longitudinally extending barrier fin ofloop-shaped cross-section having a longitudinally extending anchoringclosed end portion thereof secured to said backing strip adjacent saidpile and an opposite longitudinally extending looped end portionadjacent said free end surface of said pile.